Your profile states that you are a full time worker, full time student, and full time mom.
No you aren't.
You can only be a full time one thing,
I don't even know what it means to "whoop" a child, but I think it's really ugly.
A preschooler should take eery bit of energy you "got". That's a full time job, a preschooler.
To RockRose a person can be a full time worker and a full time student. If you take 12 hours or more in school it is considered full time. I agree with RockRose that a child of that age does take every bit of our energy. They are extra hyper at the toddler and adolescent stages. Whooping is another term for spanking that is generally used in the south.
We as parents sometimes have to evaluate our selves to see is it something that we are doing or not doing. You may want to try a child psychologist to see where the anger is steaming from. I have issues of my own that I am dealing with and it is hard not knowing what is wrong with your child. If all else fails try some type of family counseling I think that is what I am going to do.
I don't know about the snack cut off. Sounds like you have your hands full with your son and other obligations. I know it probably wears you down. Has something recently changed in his life, like a move, divorce, death, etc. Maybe that is why he is acting out.